1. The problem statement, all variables and given/known data A piece of pipe has an outer radius of 4.5cm, an inner radius of 2.8cm and length of 36cm The density of the pipe is 7.8 g/cm^3 What is the mass of this pipe? Answer is in unites of kg. 2. Relevant equations Density=mass/volume Mass= (density)(volume) Volume= mass/density 3. The attempt at a solution I subtracted the volume of the hollow inside of the tube from the large radius (2.8+4.5cm) and multiplied that by the density given. Then I converted to kg by dividing by 1000. My answer came up to be appx 40 kg. But I believe I'm wrong.